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991.
Favorable efficacy of long-term lamivudine therapy in patients with chronic hepatitis B: an 8-year follow-up study 总被引:7,自引:0,他引:7
Akuta N Suzuki F Suzuki Y Sezaki H Hosaka T Someya T Kobayashi M Saitoh S Arase Y Ikeda K Kobayashi M Kumada H 《Journal of medical virology》2005,75(4):491-498
The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used. 相似文献
992.
D. J. Schendel Ralph Oberneder Christine S. Falk Petra Jantzer Susanne Kressenstein Barbara Maget Alfons Hofstetter Gert Riethmüller Elfriede Nößner 《Journal of molecular medicine (Berlin, Germany)》1997,75(6):400-413
Renal cell carcinomas belong to the small group of tumors that are able to induce antitumor responses. Here we describe two
general types of cytotoxic effector lymphocytes that can eliminate autologous tumor cells and discuss the role that major
histocompatibility complex encoded molecules play in governing their specificities. Improved understanding of the cellular
and molecular basis of renal cell carcinoma recognition opens new avenues of research with the potential to develop better
immunotherapies for patients with metastatic disease.
Received: 24 July 1996 / Accepted: 1 November 1996 相似文献
993.
Yoshifumi Nakayama Seiji Naito Masahiro Ryuto Yasuaki Hata Mayumi Ono Katsuo Sueishi Sohtaro Komiyama Hideaki Roh Michihiko Kuwano 《Clinical & experimental metastasis》1996,14(5):466-474
We developed a modifiedin vitro invasion assay system using monolayers of vascular endothelial cells. A type I collagen gel was formed in plastic dishes, and overlaid with type IV collagen. Calf pulmonary arterial endothelial (CPAE) cells were seeded onto these plates, and incubated until they reached confluence. Five human renal cell carcinoma cell lines with various metastatic potentialsin vivo were then seeded on the monolayer CPAE cells, and their colony formation and invasion activities were examined for 9 days. At day 4, the highly metastatic cell lines increased the number of colony foci on monolayer CPAE cells several fold higher than their poorly metastatic counterpart. The horizontal spreading patterns were also different between poorly and highly metastatic cell lines. On day 9, the number of carcinoma foci that penetrated the monolayer of CPAE cells and type IV collagen sheets into type I collagen gels in highly metastatic cell lines greatly increased as compared with that of poorly metastatic cell lines. Ourin vitro invasion assay using monolayer CPAE cells would be useful to evaluate protease activities and colony formation during invasion. 相似文献
994.
W. Kong Chan Margaret M. Mole David A. Levison Richard Y Ball Qi-Long Lu Kirtika Patel Andrew M. Hanby 《The Journal of pathology》1995,177(3):241-246
The bcl-2 proto-oncogene, which inhibits programmed cell death (apoptosis), has recently been found to be cyclically expressed in human endometrium. In order to investigate its role in endometrial hyperlasia and neoplasia, bcl-2 expression was studied in 25 cases of endometrial carcinoma and 20 cases of endometrial hyperplasia (eight simple, two complex, and ten atypical hyperplasias). Uniform intense cytoplasmic bcl-2 expression was found in all cases of non-atypical hyperplasia, and less strong positivity in eight out of ten cases of atypical hyperplasia. In well-differentiated carcinomas, nine out of ten showed weak to moderate bcl-2 expression, whereas six out of seven poorly differentiated carcinomas were bcl-2-negative. Moderately differentiated tumours were an intermediate group, with six out of eight being positive. Widespread localization of bcl-2 protein to the chromosomes of dividing cells was also demonstrated, regardless of cytoplasmic bcl-2 expression, with rare staining of interphase nuclei. Our findings suggest a role for bcl-2 in the natural history of endometrial neoplasia and studies are needed to determine its usefulness as a prognostic marker. The finding of bcl-2 localization to chromosomes has important implications for its mode and site of action. 相似文献
995.
The increasing availability of means for the early detection of prostatic cancer has brought under scrutiny the criteria used for prognosis and emphasized our limitations in understanding what determines the rate of progression in these cancers. The rate of cancer cell proliferation has been under intense investigation, which, however, has yielded conflicting results. In this study we evaluated the proliferative activity of benign and neoplastic prostatic epithelium, using various existing methodologies. We first analysed the variability introduced by the methodological approach and then attempted to demonstrate whether determination of the proliferative capacity had any clinical consequence that complemented the histological grading. Tissue samples from patients, 88 with cancer and 46 with benign prostatic pathology, were studied using in vitro bromodeoxyuridine (BrdU) incorporation as well as Ki67 and the proliferating cell nuclear antigen (PCNA) to estimate the proliferative activity. Increased proliferation was found consistently in inflammation and metaplasia, but not in hyperplasia. In contrast, cancers showed marked variability. Although average proliferation indices increased with grade, there was a wide scatter of values. Correlation was stronger with stage, but also depended on the methodology. Bromodeoxyuridine indices over 10 per mille had a positive predictive value of 79 per cent for cancers extending beyond the prostatic capsule and may prove particularly helpful for evaluating patients with grade 7 cancer. This observation is significant, since grade 7 cancers are the most frequent and the least predictable. 相似文献
996.
目的:探讨诊断灰区内血清游离态前列腺特异性抗原与总前列腺特异性抗原的比值,在前列腺增生与前列腺癌的鉴别诊断中的应用价值.方法:选择血清总前列腺特异性抗原(4.0~10.0)μg/L的39例前列腺癌患者和36例前列腺增生患者,检测血清中总前列腺特异性抗原(T-PSA)和游离态前列腺特异性抗原(f-PSA),计算f/T比值.结果:T-PSA在(4.0~10.0)μg/L,组间T-PSA浓度无显著性差异(P>0.05),而(f/T)PSA比值有显著性差异(P<0.05),前列腺癌患者f/T比值明显低于前列腺增生患者(P<0.01).结论:应用f/T比值<0.16为鉴别点,提高了对前列腺癌诊断灵敏性和特异性,尤其T-PSA在(4.0~10.0)μg/L更有意义. 相似文献
997.
鼻咽癌转移相关的分泌蛋白质的筛选 总被引:2,自引:0,他引:2
目的:筛选鼻咽癌(nasopharyngeal carcinoma, NPC)转移相关的分泌蛋白质,为阐明NPC转移机制以及筛选NPC转移分子标志物提供实验依据。方法:应用二维凝胶电泳(two-dimensional electrophoresis,2-DE)技术分离一对来自同一亲本,具有不同转移潜能的NPC细胞系5-8F和6-10B细胞的分泌蛋白质,图像分析识别差异表达的蛋白质点,基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)和电喷雾-四极杆-串联质谱(ESI-Q-TOF MS/MS)对差异表达的蛋白质点进行鉴定。Western印迹法检测差异分泌蛋白质nm23-H1在两株细胞中的表达水平。结果:建立了5-8F和6-10B分泌蛋白质的2-DE图谱,质谱分析鉴定出14个非冗余的分泌蛋白质,其中Oncoprotein18等蛋白质在高转移潜能NPC细胞系5-8F中的表达水平高于无转移潜能的NPC细胞系,而nm23-H1等蛋白质在5-8F细胞系中的表达水平低于6-10B细胞系。Western印迹分析证实了nm23-H1在5-8F和6-10B细胞分泌蛋白质中的差异表达水平。结论:所鉴定的14个非冗余的差异分泌蛋白质为研究NPC转移机制以及筛选NPC转移分子标志物提供了实验依据。 相似文献
998.
Determination of the prognostic significance of cyclin B1 overexpression in patients with esophageal squamous cell carcinoma 总被引:2,自引:0,他引:2
Murakami H Furihata M Ohtsuki Y Ogoshi S 《Virchows Archiv : an international journal of pathology》1999,434(2):153-158
Recent studies have identified a family of proteins referred to as cyclins, which control the cell cycle. Cyclin B1 activates
cdc2, which regulates cell progression through the G2 and M phases. The main aim of this study was to examine the relationships
between the cyclin B1 expression in human esophageal squamous cell carcinoma (SCC) and clinicopathological factors and prognosis
of the patients. Eighty-seven cases of primary human SCC consecutively obtained at esophagectomy were immunohistochemically
studied using an anti-human cyclin B1 protein antibody (2H1-H6). The relationship between cyclin B1 expression and clinicopathological
factors, including prognosis, were also statistically assessed. Positive immunostaining of cancer cells, mainly in the cytoplasm,
was detected in 72.4% (63/87): heterogeneous pattern in 37.9 % (33/87) and homogeneous pattern in 34.5% (30/87). The prevalence
of cyclin B1 expression was significantly higher in cases with invasion deeper than the muscularis propria (P<0.005) and with venous invasion (P<0.01) than in other cases. Patients whose SCCs expressed high levels of cyclin B1 protein had a significantly poorer prognosis
than did the other patients (P<0.05). Multivariate analysis demonstrated that cyclin B1 status was an important factor affecting survival (P<0.05). These findings demonstrated that overexpression of cyclin B1 protein is associated with tumor behavior and prognosis
for patients with human esophageal SCC.
Received: 25 June 1998 / Accepted: 21 October 1998 相似文献
999.
1000.
本文探讨增强胚胎胸腺细胞抗肿瘤效应的方法。采用食管癌细胞膜抗原体外诱导培养的胚胎胸腺细胞 ;用3 H TdR掺入法检测其对食管癌细胞的细胞毒效应 ;用SP 免疫组化法检测其经诱导后细胞表面抗原的变化。结果经食管癌细胞膜抗原诱导 3~ 9d的胚胎胸腺细胞对食管癌细胞的杀伤率明显大于未经诱导的胚胎胸腺细胞 ;胚胎胸腺细胞经诱导后CD4 + /CD8+ 细胞无明显变化 ,但诱导后出现少量CD5 6细胞。食管癌细胞膜抗原体外诱导胚胎胸腺细胞可增强其对食管癌细胞的细胞毒作用 相似文献